<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>rank</title>
<link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="../../index.html" title="Chapter 1. Boost.TypeTraits">
<link rel="up" href="../reference.html" title="Alphabetical Reference">
<link rel="prev" href="promote.html" title="promote">
<link rel="next" href="remove_all_extents.html" title="remove_all_extents">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td>
<td align="center"><a href="../../../../../../index.html">Home</a></td>
<td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td>
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
<td align="center"><a href="../../../../../../more/index.htm">More</a></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="promote.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="remove_all_extents.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_typetraits.reference.rank"></a><a class="link" href="rank.html" title="rank">rank</a>
</h3></div></div></div>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">rank</span> <span class="special">:</span> <span class="keyword">public</span> <a class="link" href="integral_constant.html" title="integral_constant">integral_constant</a><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span><span class="special">,</span> <span class="identifier">RANK</span><span class="special">(</span><span class="identifier">T</span><span class="special">)&gt;</span> <span class="special">{};</span>
</pre>
<p>
        <span class="bold"><strong>Inherits:</strong></span> Class template rank inherits from
        <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">integral_constant</a><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span><span class="special">,</span> <span class="identifier">RANK</span><span class="special">(</span><span class="identifier">T</span><span class="special">)&gt;</span></code>,
        where <code class="computeroutput"><span class="identifier">RANK</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code> is the
        number of array dimensions in type <code class="computeroutput"><span class="identifier">T</span></code>.
      </p>
<p>
        If <code class="computeroutput"><span class="identifier">T</span></code> is not a (built-in)
        array type, then <code class="computeroutput"><span class="identifier">RANK</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code> is zero.
      </p>
<p>
        <span class="bold"><strong>Compiler Compatibility:</strong></span> All current compilers
        are supported by this trait.
      </p>
<p>
        <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span>
        <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">rank</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
        or <code class="computeroutput"> <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
      </p>
<p>
        <span class="bold"><strong>Examples:</strong></span>
      </p>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">[]&gt;</span></code>
          inherits from <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">integral_constant</a><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span><span class="special">,</span> <span class="number">1</span><span class="special">&gt;</span></code>.
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">[</span><span class="number">2</span><span class="special">][</span><span class="number">3</span><span class="special">][</span><span class="number">4</span><span class="special">]&gt;::</span><span class="identifier">type</span></code> is the type <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">integral_constant</a><span class="special">&lt;</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span><span class="special">,</span> <span class="number">3</span><span class="special">&gt;</span></code>.
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">[</span><span class="number">1</span><span class="special">]&gt;::</span><span class="identifier">value</span></code>
          is an integral constant expression that evaluates to <span class="emphasis"><em>1</em></span>.
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">[][</span><span class="number">2</span><span class="special">]&gt;::</span><span class="identifier">value</span></code>
          is an integral constant expression that evaluates to <span class="emphasis"><em>2</em></span>.
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">*&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
          that evaluates to <span class="emphasis"><em>0</em></span>.
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="number">3</span><span class="special">&gt;</span> <span class="special">&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
          that evaluates to <span class="emphasis"><em>0</em></span>: <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">array</span></code>
          is a class type and <span class="bold"><strong>not an array type</strong></span>!
        </p></blockquote></div>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">rank</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">value_type</span></code> is the type <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span></code>.
        </p></blockquote></div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright © 2000, 2011 Adobe Systems Inc, David Abrahams,
      Frederic Bron, Steve Cleary, Beman Dawes, Glen Fernandes, Aleksey Gurtovoy,
      Howard Hinnant, Jesse Jones, Mat Marcus, Itay Maman, John Maddock, Alexander
      Nasonov, Thorsten Ottosen, Roman Perepelitsa, Robert Ramey, Jeremy Siek, Robert
      Stewart and Steven Watanabe<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
</tr></table>
<hr>
<div class="spirit-nav">
<a accesskey="p" href="promote.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="remove_all_extents.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
</div>
</body>
</html>
